Effectiveness of Stack Ventilation in a Two-Storey House in Hot and Humid Climate

The objectives of this research were to design stack ventilation and to study its effectiveness in a two-storey house in hot and humid climate of Bangkok, Thailand Envelope openings at the rooftop and the entry door of the house were added to create height difference between inlet and outlet openings. Heat in the attic was utilized to make temperature difference in order to generate buoyancy for stack ventilation. The method of the study was experimentation in two existing houses, which had the same physical and had the most similar environment. The first house without stack ventilation was a base case. The second one was designed to integrate stack ventilation. Scientific instruments were installed in both houses at various positions. Air temperature, relative humidity and wind speed data were collected minutely for a few consecutive days for the evaluation of the experiment. It was founded that the house with stack ventilation had inside air temperature and relative humidity lower than those of the base case. The inside air temperature of the house with stack ventilation could be 0.7 Celsius lower than that of the base case. The relative humidity of the house with stack ventilation could have relative humidity of 12 % lower than that of the base case. Furthermore, the stack ventilation could make 1.06 air changes per hour with only 0.10% effective opening of building area having stack ventilation.